Intermediate dorsal cutaneous nerve of foot

At a glance

English

Intermediate dorsal cutaneous nerve of foot

Latin (TA2)

Nervus cutaneus intermedius dorsalis pedis

System

Nerve

Region

Lower limb

Side

Paired, left and right

About the intermediate dorsal cutaneous nerve of foot

The superficial fibular nerve becomes subcutaneous in the lower third of the leg and divides into two branches: the medial dorsal cutaneous nerve and the smaller intermediate dorsal cutaneous nerve, sometimes called its lateral branch. The intermediate nerve crosses the front of the ankle on its outer side, superficial to the extensor retinaculum, and runs forwards over the outer half of the foot's dorsum.

Over the foot it divides into dorsal digital nerves. One passes to the cleft between the third and fourth toes and splits for their facing sides; another passes to the cleft between the fourth and fifth toes and does the same. On its way it also gives twigs to skin on the outer side of the ankle and the outer part of the dorsum, and it joins the lateral dorsal cutaneous nerve, the continuation of the sural nerve, along the lateral border of the foot.

The superficial fibular nerve's two branches between them supply the skin over the top of all the toes except two areas: the lateral edge of the little toe, which belongs to the sural nerve, and the facing sides of the first and second toes, which belong to the deep fibular nerve. Variation is common; the intermediate nerve may be small or absent, and sural nerve branches then fill its territory. The dorsal digital nerves do not reach the tips of the toes, where the nail beds are supplied by twigs of the plantar digital nerves.

Because it lies just under the skin over the front of the ankle, the nerve can often be seen or rolled under a finger when the foot is pointed down and turned in. That same position makes it vulnerable during ankle arthroscopy, when anterolateral portals are made, and in surgery on the lateral malleolus or the fourth and fifth metatarsals. It may also be stretched in inversion sprains. Injury causes numbness, tingling or a painful neuroma over the lateral dorsum of the foot and outer toes.

Course and supply

Arises from

The superficial fibular nerve, dividing in the lower leg after it pierces the deep fascia.

Ends in

Ends as dorsal digital nerves to the facing sides of toes three and four and of toes four and five.

Supplies

Sensory to the skin of the lateral ankle, the lateral dorsum of the foot and the dorsal surfaces of the third to fifth toes.